This application is a national stage of PCT/EP00/10444 filed Oct. 24, 2000 and based upon DE 199 59 070.2 filed Dec. 8, 1999 under the International Convention.
1. Field of the Invention
The invention concerns a distribution boom for concrete pumps, with a mounting block seated on a substructure and rotatable about a vertical axis, with a multiple-arm assembly, comprised of multiple mast arms pair-wise pivotable relative to each other and carrying a cement conduit, of which the first mast arm is linked to a rotatable hinge of the mounting block, and a drive pinion rotatable about a vertical axis via a rack for the rotational drive of the mounting block.
2. Description of the Related Art
Cement distribution masts of this type are mounted on mobile or stationary substructures and have their cement line connected to the pressure connection of a concrete pump. The drive pinion is conventionally fixedly connected with the mounting block, preferably is welded permanently thereto. During assembly, the distribution boom together with drive pinion is first introduced into the drive mechanism and then screwed together with the substructure. Therein much care is necessary so that the teeth of the drive pinion and the rack are not damaged. For this reason, the assembly is usually undertaken or approached from the gear side. On the other hand, many construction sites cannot be serviced with mobile cement pumps due to their size or due to lack of space. There, stationary substructures are necessary, upon which the distribution boom is to be seated. It would thus be advantageous if the distribution boom could simply be removed from a mobile concrete pump and seated upon a stationary boom.
Beginning therewith, it is the task of the present invention to construct a distribution boom for concrete pumps, which can be simply mounted upon different substructures.
The inventive solution is based upon the concept, that the construction components associated with the drive mechanism of the distribution boom should be completely integrated in the substructure, so that a simple boom exchange is possible. In order to accomplish this, it is proposed in accordance with the invention, that the mounting block associated with the arm assembly is releasably couplable with a drive pinion associated with the substructure.
According to a preferred embodiment of the invention the drive pinion includes a coaxial alignment pin projecting above the substructure and at least one eccentric arranged or oriented rotation drive element, while the mounting block includes a receiving bushing complimentary to the alignment pin and releasably seated thereupon as well as at least one driven element releasably couplable with the rotation drive element. Herein the at least one rotation drive element is preferably associated with a preferably plate-shaped bracket or boom which projects radially beyond the locating pin. Coupling pins can be provided projecting axially parallel to the locating pin projecting above or beyond the bracket or boom, which are insertable in a complimentary driven borehole in the mounting block and there preferably are securable against being withdrawn. In the kinematic reverse, the at least one rotation drive element can also be designed as a borehole provided in the bracket axially parallel to the alignment pin, in which a complimentary driven pin of the mounting block is insertable, and is preferably restrained there against being withdrawn. The rotation drive element on the substructure side and the driven parts on the mounting block side are preferably form-fittingly couplable with each other, preferably via pins.
A preferred or advantageous further development of the invention envisions that the receiving bushing is seated with a downwardly directed opening rigidly in the mounting block, preferably is welded therein. The mounting block preferably exhibits an bracket or bracket projecting radially to the side of the bushing opening, preferably plate shaped, forming the driven part, which during the coupling process is seatable upon the bracket on the substructure side. Preferably two rotation drive elements are provided preferably diametrically opposite each other relative to the locating pin.
For simplification of assembly the locating pins, the receiving bushing and/or the at least one rotation drive element can exhibit an insertion cone for facilitating reception of the respective complimentary part.
Preferably, the inventive distribution boom is used as an interchangeable or change out boom for mobile and stationary substructures.